/**
 * Created by kule on 2017/8/14.
 */
module.exports = function arch () {
    /**
     * User agent strings that indicate a 64-bit OS.
     * See: http://stackoverflow.com/a/13709431/292185
     */
    var userAgent = navigator.userAgent
    if ([
            'x86_64',
            'x86-64',
            'Win64',
            'x64;',
            'amd64',
            'AMD64',
            'WOW64',
            'x64_64'
        ].some(function (str) {
            return userAgent.indexOf(str) > -1
        })) {
        return 'x64'
    }

    /**
     * Platform strings that indicate a 64-bit OS.
     * See: http://stackoverflow.com/a/19883965/292185
     */
    var platform = navigator.platform
    if (platform === 'MacIntel' || platform === 'Linux x86_64') {
        return 'x64'
    }

    /**
     * CPU class strings that indicate a 64-bit OS.
     * See: http://stackoverflow.com/a/6267019/292185
     */
    if (navigator.cpuClass === 'x64') {
        return 'x64'
    }

    /**
     * If none of the above, assume the architecture is 32-bit.
     */
    return 'x86'
};